#ifndef ACCOUNTSTATE_H__
#define ACCOUNTSTATE_H__

//include header
#include <covariant>

//using namespace
using namespace std;


namespace npState
{
    //class forward declaration
    class Account;
    
    class AccountState ://  public BaseClass
        public covariant
    {
        //friend
        
        //embedded type
        public: enum class ErrorEnum
            {
                AccountIsNull = 1
            };
        
        //class skeleton
        public: AccountState();
        public: AccountState(const AccountState& cpy);
        public: AccountState(AccountState&& mov) noexcept;
        public: virtual ~AccountState();
        public: AccountState& operator=(const AccountState& asn);
        public: AccountState& operator=(AccountState&& mva) noexcept;
        public: virtual shared_ptr<covariant> clone() const throw();
        public: virtual shared_ptr<covariant> steal(void* sft=nullptr) throw();

        //other constructors
        
        //public methods
        public: weak_ptr<Account> getAccount() throw();
        public: void setAccount(weak_ptr<Account> account) throw();
        public: virtual void deposit(double amount) throw(ErrorEnum) = 0;
        public: virtual void withdraw(double amount) throw(ErrorEnum) = 0;
        public: virtual void calcInterest() throw(ErrorEnum) = 0;
        public: virtual void stateCheck() throw(ErrorEnum) = 0;
        public: virtual string toString() const throw() = 0;
        
        //protected methods
        
        //private methods
        
        //protected data
        /* 类中不应该存在protected 访问级别的data
         * 要么私有，要么私有而后给出protected 访问级别的methods !!! */
        
        //private data
        /* 类中不应存在指针类型成员，
         * 取而代之，应使用智能指针予以包裹
         * 使用shared_ptr表示类拥有指针指向对象
         * 使用weak_ptr表示类仅可以使用指针指向对象
         * 智能指针对指针成员的封装和使用准则：
         * 1.类对象不允许使用unique_ptr包裹
         * 2.推敲业务逻辑，如果是共享的(share_ptr)，则尽可能少的共享指针对象
         * 3.如果从业务逻辑中发现类仅仅使用某个指针所指对象，则务必使用weak_ptr包裹指针，
         *   以此切实地描述这种使用而不拥有的关系
         * 4.类成员weak_ptr<*> ths，由其产生的，包裹this指针的，shared_ptr只允许在局部使用 */
        private: weak_ptr<Account> account;
        
        //static part
        
        //others
    };

    //inline functions
    inline AccountState::AccountState() // : BaseClass()
    {
        this->account = weak_ptr<Account>();
    }
    
    inline AccountState::AccountState(const AccountState& cpy) // : BaseClass(cpy)
    {
        this->account = cpy.account;
    }
    
    inline AccountState::AccountState(AccountState&& mov) noexcept // : BaseClass(move(mov))
    {
        this->account = move(mov.account);
    }
    
    inline AccountState::~AccountState()
    {
        
    }
    
    inline AccountState& AccountState::operator=(const AccountState& asn)
    {
        if (this == &asn)
        {
            return *this;
        }
        else
        {
            // BaseClass::operator=(asn);
            
            //To do
            this->account = asn.account;
            
            return *this;
        }
    }
    
    inline AccountState& AccountState::operator=(AccountState&& mva) noexcept
    {
        if (this == &mva)
        {
            return *this;
        }
        else
        {
            // BaseClass::operator=(move(mva));
            
            //To do
            this->account = move(mva.account);
            
            return *this;
        }
    }
    
    inline shared_ptr<covariant> AccountState::clone() const throw()
    {
        //new an instance if not abstract.
        return shared_ptr<covariant>(); //make_shared<AccountState>(*this);
    }
    
    inline shared_ptr<covariant> AccountState::steal(void* sft) throw()
    {
        AccountState* shf = static_cast<AccountState*>(sft);
        if (this == shf)
        {
            return shared_ptr<covariant>();
        }
        else
        {
            shared_ptr<AccountState> ret;
            if (!shf)
            {
                //new an instance if not abstract.
                // ret = make_shared<AccountState>();
                // shf = ret.get();
            }
            
            // BaseClass::steal(shf);
            
            //To do
            shf->account = move(this->account);
            
            return ret;
        }
    }

    inline weak_ptr<Account> AccountState::getAccount() throw()
    {
        return this->account;
    }

    inline void AccountState::setAccount(weak_ptr<Account> account) throw()
    {
        this->account = account;
    }
} // namespace npState


#endif //ACCOUNTSTATE_H__
